package com.srwl.mytx.widget;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.os.Handler;
import android.os.Vibrator;
import android.util.AttributeSet;
import android.view.FocusFinder;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.view.WindowManager;
import android.view.animation.AnimationUtils;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.OverScroller;
import android.widget.RelativeLayout;

import com.nineoldandroids.view.ViewHelper;

import java.util.List;

/**
 * Reference to ScrollView and HorizontalScrollView
 */
public class HVScrollView extends FrameLayout {
    static final int ANIMATED_SCROLL_GAP = 250;

    static final float MAX_SCROLL_FACTOR = 0.5f;


    private long mLastScroll;

    private final Rect mTempRect = new Rect();
    private OverScroller mScroller;

    /**
     * Flag to indicate that we are moving focus ourselves. This is so the
     * code that watches for focus changes initiated outside this ScrollView
     * knows that it does not have to do anything.
     */
    private boolean mScrollViewMovedFocus;

    /**
     * Position of the last motion event.
     */
    private float mLastMotionY;
    private float mLastMotionX;

    /**
     * True when the layout has changed but the traversal has not come through yet.
     * Ideally the ll_buttonView hierarchy would keep track of this for us.
     */
    private boolean mIsLayoutDirty = true;

    /**
     * The child to give focus to in the event that a child has requested focus while the
     * layout is dirty. This prevents the scroll from being wrong if the child has not been
     * laid out before requesting focus.
     */
    private View mChildToScrollTo = null;

    /**
     * True if the user is currently dragging this ScrollView around. This is
     * not the same as 'is being flinged', which can be checked by
     * mScroller.isFinished() (flinging begins when the user lifts his finger).
     */
    private boolean mIsBeingDragged = false;

    /**
     * Determines speed during touch scrolling
     */
    private VelocityTracker mVelocityTracker;

    /**
     * When set to true, the scroll ll_buttonView measure its child to make it fill the currently
     * visible area.
     */
    private boolean mFillViewport;

    /**
     * Whether arrow scrolling is animated.
     */
    private boolean mSmoothScrollingEnabled = true;

    private int mTouchSlop;
    private int mMinimumVelocity;
    private int mMaximumVelocity;

    /**
     * ID of the active pointer. This is used to retain consistency during
     * drags/flings if multiple pointers are used.
     */
    private int mActivePointerId = INVALID_POINTER;

    /**
     * Sentinel value for no current active pointer.
     * Used by {@link #mActivePointerId}.
     */
    private static final int INVALID_POINTER = -1;

    private boolean mFlingEnabled = true;
    private int currentMaxScrollX;
    private int currentMaxScrollY;
    private ScaleGestureDetector scaleGestureDetector;
    private boolean needToHandle;
    private boolean isMoving;
    private float scale;
    private float preScale = 1;
    private long lastMultiTouchTime;
    private int mDownY;
    private int mDownX;
    private int moveX;
    private int moveY;
    /**
     * DragGridView自动滚动的速度
     */
    private static final int speed = 3;
    private View mStartDragItemView;
    private Handler mHandler = new Handler();
    private Vibrator mVibrator;
    private WindowManager.LayoutParams mWindowLayoutParams;
    /**
     * 我们拖拽的item对应的Bitmap
     */
    private Bitmap mDragBitmap;
    private int mPoint2ItemLeft;
    private int mOffset2Left;
    private int mPoint2ItemTop;
    private int mOffset2Top;
    private int mStatusHeight;
    private ImageView mDragImageView;
    private WindowManager mWindowManager;
    private long dragResponseMS = 500;
    private int mTopAutoScrollBorder;
    private int mLeftAutoScrollBorder;
    private int mBottomAutoScrollBorder;
    private int mRightAutoScrollBorder;
    private boolean isLongClick;
    //长按监听
    private MyListener myListener;
    private View targetView;
    //长按滑入某item标记
    private boolean isScrollIn = true;
    //长按滑出某item标记
    private boolean isScrollOut = false;
    private int rightScrollBorder;
    private int leftScrollBorder;
    private int bottomScrollBorder;
    private int topScrollBorder;


    public HVScrollView(Context context) {
        this(context, null);
    }

    public HVScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initScrollView(context);
    }

    @Override
    protected float getTopFadingEdgeStrength() {
        if (getChildCount() == 0) {
            return 0.0f;
        }

        final int length = getVerticalFadingEdgeLength();
        if (getScrollY() < length) {
            return getScrollY() / (float) length;
        }

        return 1.0f;
    }

    @Override
    protected float getLeftFadingEdgeStrength() {
        if (getChildCount() == 0) {
            return 0.0f;
        }

        final int length = getHorizontalFadingEdgeLength();
        if (getScrollX() < length) {
            return getScrollX() / (float) length;
        }

        return 1.0f;
    }

    @Override
    protected float getRightFadingEdgeStrength() {
        if (getChildCount() == 0) {
            return 0.0f;
        }

        final int length = getHorizontalFadingEdgeLength();
        final int rightEdge = getWidth() - getPaddingRight();
        final int span = getChildAt(0).getRight() - getScrollX() - rightEdge;
        if (span < length) {
            return span / (float) length;
        }

        return 1.0f;
    }

    @Override
    protected float getBottomFadingEdgeStrength() {
        if (getChildCount() == 0) {
            return 0.0f;
        }

        final int length = getVerticalFadingEdgeLength();
        final int bottomEdge = getHeight() - getPaddingBottom();
        final int span = getChildAt(0).getBottom() - getScrollY() - bottomEdge;
        if (span < length) {
            return span / (float) length;
        }

        return 1.0f;
    }

    /**
     * @return The maximum amount this scroll ll_buttonView will scroll in response to
     * an arrow event.
     */
    public int getMaxScrollAmountV() {
        return (int) (MAX_SCROLL_FACTOR * (getBottom() - getTop()));
    }

    public int getMaxScrollAmountH() {
        return (int) (MAX_SCROLL_FACTOR * (getRight() - getLeft()));
    }


    private void initScrollView(Context context) {
        mScroller = new OverScroller(context);
        setFocusable(true);
        setDescendantFocusability(FOCUS_AFTER_DESCENDANTS);
        setWillNotDraw(false);
        final ViewConfiguration configuration = ViewConfiguration.get(getContext());
        mTouchSlop = configuration.getScaledTouchSlop();
        mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
        mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
        scaleGestureDetector = new ScaleGestureDetector(context, new ScaleGestureListener());
        mVibrator = (Vibrator) context.getSystemService(Context.VIBRATOR_SERVICE);
        mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);


        // mStatusHeight = getStatusHeight(context); //获取状态栏的高度
    }

    private void initAutoScrollBorder() {
        //获取DragGridView自动向上滚动的偏移量，小于这个值，DragGridView向下滚动
        mBottomAutoScrollBorder = getHeight() * 3 / 4;
        //获取DragGridView自动向下滚动的偏移量，大于这个值，DragGridView向上滚动
        mTopAutoScrollBorder = getHeight() / 4;
        mLeftAutoScrollBorder = getWidth() / 4;
        mRightAutoScrollBorder = getWidth() * 3 / 4;
    }

    @Override
    public void addView(View child) {
        if (getChildCount() > 0) {
            throw new IllegalStateException("ScrollView can host only one direct child");
        }

        super.addView(child);
    }

    @Override
    public void addView(View child, int index) {
        if (getChildCount() > 0) {
            throw new IllegalStateException("ScrollView can host only one direct child");
        }

        super.addView(child, index);
    }

    @Override
    public void addView(View child, ViewGroup.LayoutParams params) {
        if (getChildCount() > 0) {
            throw new IllegalStateException("ScrollView can host only one direct child");
        }

        super.addView(child, params);
    }

    @Override
    public void addView(View child, int index, ViewGroup.LayoutParams params) {
        if (getChildCount() > 0) {
            throw new IllegalStateException("ScrollView can host only one direct child");
        }

        super.addView(child, index, params);
    }

    /**
     * @return Returns true this ScrollView can be scrolled
     */
    private boolean canScrollV() {
        View child = getChildAt(0);
        if (child != null) {
            int childHeight = child.getHeight();
            return getHeight() < childHeight + getPaddingTop() + getPaddingBottom();
        }
        return false;
    }

    private boolean canScrollH() {
        View child = getChildAt(0);
        if (child != null) {
            int childWidth = child.getWidth();
            return getWidth() < childWidth + getPaddingLeft() + getPaddingRight();
        }
        return false;
    }

    /**
     * Indicates whether this ScrollView's content is stretched to fill the viewport.
     *
     * @return True if the content fills the viewport, false otherwise.
     */
    public boolean isFillViewport() {
        return mFillViewport;
    }

    /**
     * Indicates this ScrollView whether it should stretch its content height to fill
     * the viewport or not.
     *
     * @param fillViewport True to stretch the content's height to the viewport's
     *                     boundaries, false otherwise.
     */
    public void setFillViewport(boolean fillViewport) {
        if (fillViewport != mFillViewport) {
            mFillViewport = fillViewport;
            requestLayout();
        }
    }

    /**
     * @return Whether arrow scrolling will animate its transition.
     */
    public boolean isSmoothScrollingEnabled() {
        return mSmoothScrollingEnabled;
    }

    /**
     * Set whether arrow scrolling will animate its transition.
     *
     * @param smoothScrollingEnabled whether arrow scrolling will animate its transition
     */
    public void setSmoothScrollingEnabled(boolean smoothScrollingEnabled) {
        mSmoothScrollingEnabled = smoothScrollingEnabled;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        if (!mFillViewport) {
            return;
        }

        final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        if (heightMode == MeasureSpec.UNSPECIFIED && widthMode == MeasureSpec.UNSPECIFIED) {
            return;
        }

        if (getChildCount() > 0) {
            final View child = getChildAt(0);
            int height = getMeasuredHeight();
            int width = getMeasuredWidth();
            if (child.getMeasuredHeight() < height || child.getMeasuredWidth() < width) {
                width -= getPaddingLeft();
                width -= getPaddingRight();

                int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(width, MeasureSpec.EXACTLY);// getChildMeasureSpec()

                height -= getPaddingTop();
                height -= getPaddingBottom();
                int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);

                child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
            }
        }
    }

    @Override
    public boolean dispatchKeyEvent(KeyEvent event) {
        // Let the focused ll_buttonView and/or our descendants get the key first
        return super.dispatchKeyEvent(event) || executeKeyEvent(event);
    }

    /**
     * You can call this function yourself to have the scroll ll_buttonView perform
     * scrolling from a key event, just as if the event had been dispatched to
     * it by the ll_buttonView hierarchy.
     *
     * @param event The key event to execute.
     * @return Return true if the event was handled, else false.
     */
    public boolean executeKeyEvent(KeyEvent event) {
        mTempRect.setEmpty();

        boolean handled = false;

        if (event.getAction() == KeyEvent.ACTION_DOWN) {
            switch (event.getKeyCode()) {
                case KeyEvent.KEYCODE_DPAD_LEFT:
                    if (canScrollH()) {
                        if (!event.isAltPressed()) {
                            handled = arrowScrollH(View.FOCUS_LEFT);
                        } else {
                            handled = fullScrollH(View.FOCUS_LEFT);
                        }
                    }
                    break;
                case KeyEvent.KEYCODE_DPAD_RIGHT:
                    if (canScrollH()) {
                        if (!event.isAltPressed()) {
                            handled = arrowScrollH(View.FOCUS_RIGHT);
                        } else {
                            handled = fullScrollH(View.FOCUS_RIGHT);
                        }
                    }
                    break;
                case KeyEvent.KEYCODE_DPAD_UP:
                    if (canScrollV()) {
                        if (!event.isAltPressed()) {
                            handled = arrowScrollV(View.FOCUS_UP);
                        } else {
                            handled = fullScrollV(View.FOCUS_UP);
                        }
                    }
                    break;
                case KeyEvent.KEYCODE_DPAD_DOWN:
                    if (canScrollV()) {
                        if (!event.isAltPressed()) {
                            handled = arrowScrollV(View.FOCUS_DOWN);
                        } else {
                            handled = fullScrollV(View.FOCUS_DOWN);
                        }
                    }
                    break;
            }
        }
        return handled;
    }

    private boolean inChild(int x, int y) {
        if (getChildCount() > 0) {
            final int scrollX = getScrollX();
            final int scrollY = getScrollY();
            final View child = getChildAt(0);
            return !(y < child.getTop() - scrollY
                    || y >= child.getBottom() - scrollY
                    || x < child.getLeft() - scrollX
                    || x >= child.getRight() - scrollX);
        }
        return false;
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mDownX = (int) ev.getX();
                mDownY = (int) ev.getY();
                mStartDragItemView = getPointView(mDownX, mDownY);
                //为空说明点击没在任何一个item上
                if (mStartDragItemView == null) {
                    break;
                }
                mStartDragItemView.setVisibility(INVISIBLE);
                //使用Handler延迟dragResponseMS执行mLongClickRunnable
                mHandler.postDelayed(mLongClickRunnable, dragResponseMS);
                getPointOffsetofItem(mDownX, mDownY, mStartDragItemView);
                //手指点击处与点击view的上边缘和左边缘的距离
//                float y = mStartDragItemView.getY();
//                mPoint2ItemTop = (int) (mDownY- y);
//                mPoint2ItemLeft = (int) (mDownX- mStartDragItemView.getX());
                //HVScrollView与屏幕上边、左边的距离
                mOffset2Top = (int) (ev.getRawY() - mDownY);
                mOffset2Left = (int) (ev.getRawX() - mDownX);

                //开启mDragItemView绘图缓存
                mStartDragItemView.setDrawingCacheEnabled(true);
                //获取mDragItemView在缓存中的Bitmap对象
                mDragBitmap = Bitmap.createBitmap(mStartDragItemView.getDrawingCache());
                //这一步很关键，释放绘图缓存，避免出现重复的镜像
                mStartDragItemView.destroyDrawingCache();

                break;
            case MotionEvent.ACTION_MOVE:
                int moveX = (int) ev.getX();
                int moveY = (int) ev.getY();


                //滑动超过item的边界，移除前天添加到handler的mLongClickRunnable，长按时间不足1S，就中断长按事件的执行,且：如果长按事件已经激活，也没有必要再去remove了
                if (isPointOutItem(moveX, moveY, mStartDragItemView) && !isLongClick) {
                    mHandler.removeCallbacks(mLongClickRunnable);
                }
                break;

            case MotionEvent.ACTION_UP:
                mHandler.removeCallbacks(mLongClickRunnable);
                mHandler.removeCallbacks(mScrollRunnable);
                break;
        }

        return super.dispatchTouchEvent(ev);
    }


    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {

        final int action = ev.getAction();
//        if ((action == MotionEvent.ACTION_MOVE) && (mIsBeingDragged)) {
//            return true;
//        }

        switch (action & MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_MOVE: {

//                final int activePointerId = mActivePointerId;
//                if (activePointerId == INVALID_POINTER) {
//                    // If we don't have a valid id, the touch down wasn't on content.
//                    break;
//                }
//
//                final int pointerIndex = ev.findPointerIndex(activePointerId);
//                final float y = ev.getY(pointerIndex);
//                final int yDiff = (int) Math.abs(y - mLastMotionY);
//                if (yDiff > mTouchSlop) {
//                    mIsBeingDragged = true;
//                    mLastMotionY = y;
//                }
//                final float x = ev.getX(pointerIndex);
//                final int xDiff = (int) Math.abs(x - mLastMotionX);
//                if (xDiff > mTouchSlop) {
//                    mIsBeingDragged = true;
//                    mLastMotionX = x;
//                }
                if (isLongClick) {
                    mIsBeingDragged = true;
                } else {
                    mIsBeingDragged = false;
                }
                break;
            }

            case MotionEvent.ACTION_DOWN: {
                final float x = ev.getX();
                final float y = ev.getY();
                if (!inChild((int) x, (int) y)) {
                    mIsBeingDragged = false;
                    break;
                }


                mLastMotionY = y;
                mLastMotionX = x;
                mActivePointerId = ev.getPointerId(0);


                mIsBeingDragged = !mScroller.isFinished();
                break;
            }

            case MotionEvent.ACTION_CANCEL:
            case MotionEvent.ACTION_UP:

                mIsBeingDragged = false;
                mActivePointerId = INVALID_POINTER;
                break;
            case MotionEvent.ACTION_POINTER_UP:
                onSecondaryPointerUp(ev);
                break;
        }

        return mIsBeingDragged;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {

        int pointerCount = event.getPointerCount(); // 获得多少点
        if (pointerCount > 1) {// 多点触控，
            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    needToHandle = true;
                    break;
                case MotionEvent.ACTION_MOVE:

                    break;
                case MotionEvent.ACTION_POINTER_2_UP://第二个手指抬起的时候
                    needToHandle = true;
                    break;

                default:
                    break;
            }
            return scaleGestureDetector.onTouchEvent(event);//让mScaleGestureDetector处理触摸事件
        } else {
            long currentMultiTouchTime = System.currentTimeMillis();
            if (currentMultiTouchTime - lastMultiTouchTime < 200) {
                return false;
            }
            if (event.getAction() == MotionEvent.ACTION_DOWN && event.getEdgeFlags() != 0) {
                // Don't handle edge touches immediately -- they may actually belong to one of our
                // descendants.
                return false;
            }

            if (mVelocityTracker == null) {
                mVelocityTracker = VelocityTracker.obtain();
            }
            mVelocityTracker.addMovement(event);

            final int action = event.getAction();

            switch (action & MotionEvent.ACTION_MASK) {
                case MotionEvent.ACTION_DOWN: {
                    isMoving = false;
                    final float x = event.getX();
                    final float y = event.getY();
                    if (!(mIsBeingDragged = inChild((int) x, (int) y))) {
                        return false;
                    }

                    if (!mScroller.isFinished()) {
                        mScroller.abortAnimation();
                    }

                    mLastMotionY = y;
                    mLastMotionX = x;
                    mActivePointerId = event.getPointerId(0);
                    break;
                }
                case MotionEvent.ACTION_MOVE:
                    isMoving = true;
                    moveX = (int) event.getX();
                    moveY = (int) event.getY();
                    if (isLongClick) {
                        onDragItem(moveX, moveY);
                    }
                    if (mIsBeingDragged && !isLongClick) {
                        // Scroll to follow the motion event
                        final int activePointerIndex = event.findPointerIndex(mActivePointerId);
                        final int deltaY = (int) (mLastMotionY - moveY);
                        mLastMotionY = moveY;

                        final int deltaX = (int) (mLastMotionX - moveX);
                        mLastMotionX = moveX;

                        scrollBy(deltaX, deltaY);

                    }
                    break;
                case MotionEvent.ACTION_UP:
                    isMoving = false;
                    int currentX = (int) event.getX();
                    int currentY = (int) event.getY();


                    if (mIsBeingDragged && !isLongClick) {
                        if (mFlingEnabled) {
//                            final VelocityTracker velocityTracker = mVelocityTracker;
//                            velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
                            mVelocityTracker.computeCurrentVelocity(1000);
                            int initialVelocitx = (int) mVelocityTracker.getXVelocity();
                            int initialVelocity = (int) mVelocityTracker.getYVelocity();
                            //                  int initialVelocitx = (int) velocityTracker.getXVelocity(mActivePointerId);
                            //                  int initialVelocity = (int) velocityTracker.getYVelocity(mActivePointerId);


                            if (Math.abs(initialVelocitx) > mMinimumVelocity || Math.abs(initialVelocity) > mMinimumVelocity) {
                                computeMove(currentX, currentY, -initialVelocitx, -initialVelocity);
                            } else {
                                if (mScroller.springBack(getScrollX(), getScrollY(), 0, rightScrollBorder, 0, bottomScrollBorder)) {
                                    postInvalidateOnAnimation();
                                }
                            }
                            //  computeMove(x, y, -initialVelocitx, -initialVelocity);


                        }

                        mActivePointerId = INVALID_POINTER;
                        mIsBeingDragged = false;

                        if (mVelocityTracker != null) {
                            mVelocityTracker.recycle();
                            mVelocityTracker = null;
                        }
                    }
                    if (isLongClick) {
                        onStopDrag(currentX, currentY);
                        isLongClick = false;

                    }
                    break;
                case MotionEvent.ACTION_CANCEL:
                    isMoving = false;
                    if (mIsBeingDragged && getChildCount() > 0) {
                        mActivePointerId = INVALID_POINTER;
                        mIsBeingDragged = false;
                        if (mVelocityTracker != null) {
                            mVelocityTracker.recycle();
                            mVelocityTracker = null;
                        }
                    }
                    break;
                case MotionEvent.ACTION_POINTER_UP:
                    onSecondaryPointerUp(event);
                    break;
            }
            return true;
        }

    }

    private void onSecondaryPointerUp(MotionEvent ev) {
        final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_ID_MASK) >>
                MotionEvent.ACTION_POINTER_ID_SHIFT;
        final int pointerId = ev.getPointerId(pointerIndex);
        if (pointerId == mActivePointerId) {
            // This was our active pointer going up. Choose a new
            // active pointer and adjust accordingly.
            final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
            mLastMotionX = ev.getX(newPointerIndex);
            mLastMotionY = ev.getY(newPointerIndex);
            mActivePointerId = ev.getPointerId(newPointerIndex);
            if (mVelocityTracker != null) {
                mVelocityTracker.clear();
            }
        }
    }

    /**
     * <p>
     * Finds the next focusable component that fits in the specified bounds.
     * </p>
     *
     * @param topFocus look for a candidate is the one at the top of the bounds
     *                 if topFocus is true, or at the bottom of the bounds if topFocus is
     *                 false
     * @param top      the top offset of the bounds in which a focusable must be
     *                 found
     * @param bottom   the bottom offset of the bounds in which a focusable must
     *                 be found
     * @return the next focusable component in the bounds or null if none can
     * be found
     */
    private View findFocusableViewInBoundsV(boolean topFocus, int top, int bottom) {

        List<View> focusables = getFocusables(View.FOCUS_FORWARD);
        View focusCandidate = null;

         /*
          * A fully contained focusable is one where its top is below the bound's
          * top, and its bottom is above the bound's bottom. A partially
          * contained focusable is one where some part of it is within the
          * bounds, but it also has some part that is not within bounds.  A fully contained
          * focusable is preferred to a partially contained focusable.
          */
        boolean foundFullyContainedFocusable = false;

        int count = focusables.size();
        for (int i = 0; i < count; i++) {
            View view = focusables.get(i);
            int viewTop = view.getTop();
            int viewBottom = view.getBottom();

            if (top < viewBottom && viewTop < bottom) {
                 /*
                  * the focusable is in the target area, it is a candidate for
                  * focusing
                  */

                final boolean viewIsFullyContained = (top < viewTop) &&
                        (viewBottom < bottom);

                if (focusCandidate == null) {
                     /* No candidate, take this one */
                    focusCandidate = view;
                    foundFullyContainedFocusable = viewIsFullyContained;
                } else {
                    final boolean viewIsCloserToBoundary =
                            (topFocus && viewTop < focusCandidate.getTop()) ||
                                    (!topFocus && viewBottom > focusCandidate
                                            .getBottom());

                    if (foundFullyContainedFocusable) {
                        if (viewIsFullyContained && viewIsCloserToBoundary) {
                             /*
                              * We're dealing with only fully contained views, so
                              * it has to be closer to the boundary to beat our
                              * candidate
                              */
                            focusCandidate = view;
                        }
                    } else {
                        if (viewIsFullyContained) {
                             /* Any fully contained ll_buttonView beats a partially contained ll_buttonView */
                            focusCandidate = view;
                            foundFullyContainedFocusable = true;
                        } else if (viewIsCloserToBoundary) {
                             /*
                              * Partially contained ll_buttonView beats another partially
                              * contained ll_buttonView if it's closer
                              */
                            focusCandidate = view;
                        }
                    }
                }
            }
        }

        return focusCandidate;
    }

    private View findFocusableViewInBoundsH(boolean leftFocus, int left, int right) {

        List<View> focusables = getFocusables(View.FOCUS_FORWARD);
        View focusCandidate = null;

         /*
          * A fully contained focusable is one where its left is below the bound's
          * left, and its right is above the bound's right. A partially
          * contained focusable is one where some part of it is within the
          * bounds, but it also has some part that is not within bounds.  A fully contained
          * focusable is preferred to a partially contained focusable.
          */
        boolean foundFullyContainedFocusable = false;

        int count = focusables.size();
        for (int i = 0; i < count; i++) {
            View view = focusables.get(i);
            int viewLeft = view.getLeft();
            int viewRight = view.getRight();

            if (left < viewRight && viewLeft < right) {
                 /*
                  * the focusable is in the target area, it is a candidate for
                  * focusing
                  */

                final boolean viewIsFullyContained = (left < viewLeft) &&
                        (viewRight < right);

                if (focusCandidate == null) {
                     /* No candidate, take this one */
                    focusCandidate = view;
                    foundFullyContainedFocusable = viewIsFullyContained;
                } else {
                    final boolean viewIsCloserToBoundary =
                            (leftFocus && viewLeft < focusCandidate.getLeft()) ||
                                    (!leftFocus && viewRight > focusCandidate.getRight());

                    if (foundFullyContainedFocusable) {
                        if (viewIsFullyContained && viewIsCloserToBoundary) {
                             /*
                              * We're dealing with only fully contained views, so
                              * it has to be closer to the boundary to beat our
                              * candidate
                              */
                            focusCandidate = view;
                        }
                    } else {
                        if (viewIsFullyContained) {
                             /* Any fully contained ll_buttonView beats a partially contained ll_buttonView */
                            focusCandidate = view;
                            foundFullyContainedFocusable = true;
                        } else if (viewIsCloserToBoundary) {
                             /*
                              * Partially contained ll_buttonView beats another partially
                              * contained ll_buttonView if it's closer
                              */
                            focusCandidate = view;
                        }
                    }
                }
            }
        }

        return focusCandidate;
    }

    /**
     * <p>Handles scrolling in response to a "home/end" shortcut press. This
     * method will scroll the ll_buttonView to the top or bottom and give the focus
     * to the topmost/bottommost component in the new visible area. If no
     * component is a good candidate for focus, this scrollview reclaims the
     * focus.</p>
     *
     * @param direction the scroll direction: {@link }
     *                  to go the top of the ll_buttonView or
     *                  {@link } to go the bottom
     * @return true if the key event is consumed by this method, false otherwise
     */
    public boolean fullScrollV(int direction) {
        boolean down = direction == View.FOCUS_DOWN;
        int height = getHeight();

        mTempRect.top = 0;
        mTempRect.bottom = height;

        if (down) {
            int count = getChildCount();
            if (count > 0) {
                View view = getChildAt(count - 1);
                mTempRect.bottom = view.getBottom();
                mTempRect.top = mTempRect.bottom - height;
            }
        }

        return scrollAndFocusV(direction, mTempRect.top, mTempRect.bottom);
    }

    public boolean fullScrollH(int direction) {
        boolean right = direction == View.FOCUS_RIGHT;
        int width = getWidth();

        mTempRect.left = 0;
        mTempRect.right = width;

        if (right) {
            int count = getChildCount();
            if (count > 0) {
                View view = getChildAt(0);
                mTempRect.right = view.getRight();
                mTempRect.left = mTempRect.right - width;
            }
        }

        return scrollAndFocusH(direction, mTempRect.left, mTempRect.right);
    }

    /**
     * <p>Scrolls the ll_buttonView to make the area defined by <code>top</code> and
     * <code>bottom</code> visible. This method attempts to give the focus
     * to a component visible in this area. If no component can be focused in
     * the new visible area, the focus is reclaimed by this scrollview.</p>
     *
     * @param direction the scroll direction: {@link android.view}
     *                  to go upward
     *                  {@link android.view FOCUS_DOWN} to downward
     * @param top       the top offset of the new area to be made visible
     * @param bottom    the bottom offset of the new area to be made visible
     * @return true if the key event is consumed by this method, false otherwise
     */
    private boolean scrollAndFocusV(int direction, int top, int bottom) {
        boolean handled = true;

        int height = getHeight();
        int containerTop = getScrollY();
        int containerBottom = containerTop + height;
        boolean up = direction == View.FOCUS_UP;

        View newFocused = findFocusableViewInBoundsV(up, top, bottom);
        if (newFocused == null) {
            newFocused = this;
        }

        if (top >= containerTop && bottom <= containerBottom) {
            handled = false;
        } else {
            int delta = up ? (top - containerTop) : (bottom - containerBottom);
            doScrollY(delta);
        }

        if (newFocused != findFocus() && newFocused.requestFocus(direction)) {
            mScrollViewMovedFocus = true;
            mScrollViewMovedFocus = false;
        }

        return handled;
    }

    private boolean scrollAndFocusH(int direction, int left, int right) {
        boolean handled = true;

        int width = getWidth();
        int containerLeft = getScrollX();
        int containerRight = containerLeft + width;
        boolean goLeft = direction == View.FOCUS_LEFT;

        View newFocused = findFocusableViewInBoundsH(goLeft, left, right);
        if (newFocused == null) {
            newFocused = this;
        }

        if (left >= containerLeft && right <= containerRight) {
            handled = false;
        } else {
            int delta = goLeft ? (left - containerLeft) : (right - containerRight);
            doScrollX(delta);
        }

        if (newFocused != findFocus() && newFocused.requestFocus(direction)) {
            mScrollViewMovedFocus = true;
            mScrollViewMovedFocus = false;
        }

        return handled;
    }

    /**
     * Handle scrolling in response to an up or down arrow click.
     *
     * @param direction The direction corresponding to the arrow key that was
     *                  pressed
     * @return True if we consumed the event, false otherwise
     */
    public boolean arrowScrollV(int direction) {

        View currentFocused = findFocus();
        if (currentFocused == this) currentFocused = null;

        View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);

        final int maxJump = getMaxScrollAmountV();

        if (nextFocused != null && isWithinDeltaOfScreenV(nextFocused, maxJump, getHeight())) {
            nextFocused.getDrawingRect(mTempRect);
            offsetDescendantRectToMyCoords(nextFocused, mTempRect);
            int scrollDelta = computeScrollDeltaToGetChildRectOnScreenV(mTempRect);
            doScrollY(scrollDelta);
            nextFocused.requestFocus(direction);
        } else {
            // no new focus
            int scrollDelta = maxJump;

            if (direction == View.FOCUS_UP && getScrollY() < scrollDelta) {
                scrollDelta = getScrollY();
            } else if (direction == View.FOCUS_DOWN) {
                if (getChildCount() > 0) {
                    int daBottom = getChildAt(0).getBottom();

                    int screenBottom = getScrollY() + getHeight();

                    if (daBottom - screenBottom < maxJump) {
                        scrollDelta = daBottom - screenBottom;
                    }
                }
            }
            if (scrollDelta == 0) {
                return false;
            }
            doScrollY(direction == View.FOCUS_DOWN ? scrollDelta : -scrollDelta);
        }

        if (currentFocused != null && currentFocused.isFocused()
                && isOffScreenV(currentFocused)) {
            // previously focused item still has focus and is off screen, give
            // it up (take it back to ourselves)
            // (also, need to temporarily force FOCUS_BEFORE_DESCENDANTS so we are
            // sure to
            // get it)
            final int descendantFocusability = getDescendantFocusability();  // save
            setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
            requestFocus();
            setDescendantFocusability(descendantFocusability);  // restore
        }
        return true;
    }

    public boolean arrowScrollH(int direction) {

        View currentFocused = findFocus();
        if (currentFocused == this) currentFocused = null;

        View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);

        final int maxJump = getMaxScrollAmountH();

        if (nextFocused != null && isWithinDeltaOfScreenH(nextFocused, maxJump)) {
            nextFocused.getDrawingRect(mTempRect);
            offsetDescendantRectToMyCoords(nextFocused, mTempRect);
            int scrollDelta = computeScrollDeltaToGetChildRectOnScreenH(mTempRect);
            doScrollX(scrollDelta);
            nextFocused.requestFocus(direction);
        } else {
            // no new focus
            int scrollDelta = maxJump;

            if (direction == View.FOCUS_LEFT && getScrollX() < scrollDelta) {
                scrollDelta = getScrollX();
            } else if (direction == View.FOCUS_RIGHT && getChildCount() > 0) {

                int daRight = getChildAt(0).getRight();

                int screenRight = getScrollX() + getWidth();

                if (daRight - screenRight < maxJump) {
                    scrollDelta = daRight - screenRight;
                }
            }
            if (scrollDelta == 0) {
                return false;
            }
            doScrollX(direction == View.FOCUS_RIGHT ? scrollDelta : -scrollDelta);
        }

        if (currentFocused != null && currentFocused.isFocused()
                && isOffScreenH(currentFocused)) {
            // previously focused item still has focus and is off screen, give
            // it up (take it back to ourselves)
            // (also, need to temporarily force FOCUS_BEFORE_DESCENDANTS so we are
            // sure to
            // get it)
            final int descendantFocusability = getDescendantFocusability();  // save
            setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
            requestFocus();
            setDescendantFocusability(descendantFocusability);  // restore
        }
        return true;
    }

    /**
     * @return whether the descendant of this scroll ll_buttonView is scrolled off
     * screen.
     */
    private boolean isOffScreenV(View descendant) {
        return !isWithinDeltaOfScreenV(descendant, 0, getHeight());
    }

    private boolean isOffScreenH(View descendant) {
        return !isWithinDeltaOfScreenH(descendant, 0);
    }

    /**
     * @return whether the descendant of this scroll ll_buttonView is within delta
     * pixels of being on the screen.
     */
    private boolean isWithinDeltaOfScreenV(View descendant, int delta, int height) {
        descendant.getDrawingRect(mTempRect);
        offsetDescendantRectToMyCoords(descendant, mTempRect);

        return (mTempRect.bottom + delta) >= getScrollY()
                && (mTempRect.top - delta) <= (getScrollY() + height);
    }

    private boolean isWithinDeltaOfScreenH(View descendant, int delta) {
        descendant.getDrawingRect(mTempRect);
        offsetDescendantRectToMyCoords(descendant, mTempRect);

        return (mTempRect.right + delta) >= getScrollX()
                && (mTempRect.left - delta) <= (getScrollX() + getWidth());
    }

    /**
     * Smooth scroll by a Y delta
     *
     * @param delta the number of pixels to scroll by on the Y axis
     */
    private void doScrollY(int delta) {
        if (delta != 0) {
            if (mSmoothScrollingEnabled) {
                smoothScrollBy(0, delta);
            } else {
                scrollBy(0, delta);
            }
        }
    }

    private void doScrollX(int delta) {
        if (delta != 0) {
            if (mSmoothScrollingEnabled) {
                smoothScrollBy(delta, 0);
            } else {
                scrollBy(delta, 0);
            }
        }
    }

    /**
     * Like {@link View#scrollBy}, but scroll smoothly instead of immediately.
     *
     * @param dx the number of pixels to scroll by on the X axis
     * @param dy the number of pixels to scroll by on the Y axis
     */
    public void smoothScrollBy(int dx, int dy) {
        if (getChildCount() == 0) {
            // Nothing to do.
            return;
        }
        long duration = AnimationUtils.currentAnimationTimeMillis() - mLastScroll;
        if (duration > ANIMATED_SCROLL_GAP) {
            final int height = getHeight() - getPaddingBottom() - getPaddingTop();
            final int bottom = getChildAt(0).getHeight();
            final int maxY = Math.max(0, bottom - height);
            final int scrollY = getScrollY();
            dy = Math.max(0, Math.min(scrollY + dy, maxY)) - scrollY;

            final int width = getWidth() - getPaddingRight() - getPaddingLeft();
            final int right = getChildAt(0).getWidth();
            final int maxX = Math.max(0, right - width);
            final int scrollX = getScrollX();
            dx = Math.max(0, Math.min(scrollX + dx, maxX)) - scrollX;

            mScroller.startScroll(scrollX, scrollY, dx, dy);
            invalidate();
        } else {
            if (!mScroller.isFinished()) {
                mScroller.abortAnimation();
            }
            scrollBy(dx, dy);
        }
        mLastScroll = AnimationUtils.currentAnimationTimeMillis();
    }

    /**
     * Like {@link #scrollTo}, but scroll smoothly instead of immediately.
     *
     * @param x the position where to scroll on the X axis
     * @param y the position where to scroll on the Y axis
     */
    public final void smoothScrollTo(int x, int y) {

        currentMaxScrollX = x;
        currentMaxScrollY = y;
        if (!mScroller.isFinished()) {
            return;
        }
        int scrollX = getScrollX();
        int scrollY = getScrollY();
        int deltaX = x - leftScrollBorder - scrollX;
        int deltaY = y - topScrollBorder - scrollY;
        //如果containView此次添加的item位置是在负方向的（item左顶点坐标至少有一个是负数），这儿就让containView就回到原点，

        if (x < 0) {
            deltaX = 0 - scrollX;
        }
        if (y < 0) {
            deltaY = 0 - scrollY;
        }
        if (deltaX != 0 || deltaY != 0) {
            mScroller.startScroll(scrollX, scrollY, deltaX, deltaY, 1000);
        }
        invalidate();
    }

    /**
     * <p>The scroll range of a scroll ll_buttonView is the overall height of all of its
     * children.</p>
     */
    @Override
    protected int computeVerticalScrollRange() {
        final int count = getChildCount();
        final int contentHeight = getHeight() - getPaddingBottom() - getPaddingTop();
        if (count == 0) {
            return contentHeight;
        }

        return getChildAt(0).getBottom();
    }

    @Override
    protected int computeHorizontalScrollRange() {
        final int count = getChildCount();
        final int contentWidth = getWidth() - getPaddingLeft() - getPaddingRight();
        if (count == 0) {
            return contentWidth;
        }

        return getChildAt(0).getRight();
    }

    @Override
    protected int computeVerticalScrollOffset() {
        return Math.max(0, super.computeVerticalScrollOffset());
    }

    @Override
    protected int computeHorizontalScrollOffset() {
        return Math.max(0, super.computeHorizontalScrollOffset());
    }

    @Override
    protected void measureChild(View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec) {
        int childWidthMeasureSpec;
        int childHeightMeasureSpec;

        childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);

        childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);

        child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
    }

    @Override
    protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed,
                                           int parentHeightMeasureSpec, int heightUsed) {
        final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();

        final int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
                lp.leftMargin + lp.rightMargin, MeasureSpec.UNSPECIFIED);
        final int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
                lp.topMargin + lp.bottomMargin, MeasureSpec.UNSPECIFIED);

        child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
    }

    @Override
    public void computeScroll() {
        if (mScroller.computeScrollOffset()) {
            // This is called at drawing time by ViewGroup.  We don't want to
            // re-show the scrollbars at this point, which scrollTo will do,
            // so we replicate most of scrollTo here.
            //
            //         It's a little odd to call onScrollChanged from inside the drawing.
            //
            //         It is, except when you remember that computeScroll() is used to
            //         animate scrolling. So unless we want to defer the onScrollChanged()
            //         until the end of the animated scrolling, we don't really have a
            //         choice here.
            //
            //         I agree.  The alternative, which I think would be worse, is to post
            //         something and tell the subclasses later.  This is bad because there
            //         will be a window where mScrollX/Y is different from what the app
            //         thinks it is.
            //
            int x = mScroller.getCurrX();
            int y = mScroller.getCurrY();
            super.scrollTo(x, y);
//            if (getChildCount() > 0) {
//                View child = getChildAt(0);
//                x = clamp(x, getWidth() - getPaddingRight() - getPaddingLeft(), child.getWidth());
//                y = clamp(y, getHeight() - getPaddingBottom() - getPaddingTop(), child.getHeight());
//                super.scrollTo(x, y);
//            }
            awakenScrollBars();

            // Keep on drawing until the animation has finished.
            postInvalidate();
        } else if (!isMoving) {
//            if (isNeedScrollBack()) {
//                postInvalidate();
//            }
//            mScroller.springBack(getScrollX(),getScrollY(),0,currentMaxScrollX,0,currentMaxScrollY);
//            postInvalidateOnAnimation();
        }
    }

    /**
     * Scrolls the ll_buttonView to the given child.
     *
     * @param child the View to scroll to
     */
    private void scrollToChild(View child) {
        child.getDrawingRect(mTempRect);

         /* Offset from child's local coordinates to ScrollView coordinates */
        offsetDescendantRectToMyCoords(child, mTempRect);

        int scrollDeltaV = computeScrollDeltaToGetChildRectOnScreenV(mTempRect);
        int scrollDeltaH = computeScrollDeltaToGetChildRectOnScreenH(mTempRect);

        if (scrollDeltaH != 0 || scrollDeltaV != 0) {
            scrollBy(scrollDeltaH, scrollDeltaV);
        }
    }

    /**
     * If rect is off screen, scroll just enough to get it (or at least the
     * first screen size chunk of it) on screen.
     *
     * @param rect      The rectangle.
     * @param immediate True to scroll immediately without animation
     * @return true if scrolling was performed
     */
    private boolean scrollToChildRect(Rect rect, boolean immediate) {
        final int deltaV = computeScrollDeltaToGetChildRectOnScreenV(rect);
        final int deltaH = computeScrollDeltaToGetChildRectOnScreenH(rect);
        final boolean scroll = deltaH != 0 || deltaV != 0;
        if (scroll) {
            if (immediate) {
                scrollBy(deltaH, deltaV);
            } else {
                smoothScrollBy(deltaH, deltaV);
            }
        }
        return scroll;
    }

    /**
     * Compute the amount to scroll in the Y direction in order to get
     * a rectangle completely on the screen (or, if taller than the screen,
     * at least the first screen size chunk of it).
     *
     * @param rect The rect.
     * @return The scroll delta.
     */
    protected int computeScrollDeltaToGetChildRectOnScreenV(Rect rect) {
        if (getChildCount() == 0) return 0;

        int height = getHeight();
        int screenTop = getScrollY();
        int screenBottom = screenTop + height;

        int fadingEdge = getVerticalFadingEdgeLength();

        // leave room for top fading edge as long as rect isn't at very top
        if (rect.top > 0) {
            screenTop += fadingEdge;
        }

        // leave room for bottom fading edge as long as rect isn't at very bottom
        if (rect.bottom < getChildAt(0).getHeight()) {
            screenBottom -= fadingEdge;
        }

        int scrollYDelta = 0;

        if (rect.bottom > screenBottom && rect.top > screenTop) {
            // need to move down to get it in ll_buttonView: move down just enough so
            // that the entire rectangle is in ll_buttonView (or at least the first
            // screen size chunk).

            if (rect.height() > height) {
                // just enough to get screen size chunk on
                scrollYDelta += (rect.top - screenTop);
            } else {
                // get entire rect at bottom of screen
                scrollYDelta += (rect.bottom - screenBottom);
            }

            // make sure we aren't scrolling beyond the end of our content
            int bottom = getChildAt(0).getBottom();
            int distanceToBottom = bottom - screenBottom;
            scrollYDelta = Math.min(scrollYDelta, distanceToBottom);

        } else if (rect.top < screenTop && rect.bottom < screenBottom) {
            // need to move up to get it in ll_buttonView: move up just enough so that
            // entire rectangle is in ll_buttonView (or at least the first screen
            // size chunk of it).

            if (rect.height() > height) {
                // screen size chunk
                scrollYDelta -= (screenBottom - rect.bottom);
            } else {
                // entire rect at top
                scrollYDelta -= (screenTop - rect.top);
            }

            // make sure we aren't scrolling any further than the top our content
            scrollYDelta = Math.max(scrollYDelta, -getScrollY());
        }
        return scrollYDelta;
    }

    protected int computeScrollDeltaToGetChildRectOnScreenH(Rect rect) {
        if (getChildCount() == 0) return 0;

        int width = getWidth();
        int screenLeft = getScrollX();
        int screenRight = screenLeft + width;

        int fadingEdge = getHorizontalFadingEdgeLength();

        // leave room for left fading edge as long as rect isn't at very left
        if (rect.left > 0) {
            screenLeft += fadingEdge;
        }

        // leave room for right fading edge as long as rect isn't at very right
        if (rect.right < getChildAt(0).getWidth()) {
            screenRight -= fadingEdge;
        }

        int scrollXDelta = 0;

        if (rect.right > screenRight && rect.left > screenLeft) {
            // need to move right to get it in ll_buttonView: move right just enough so
            // that the entire rectangle is in ll_buttonView (or at least the first
            // screen size chunk).

            if (rect.width() > width) {
                // just enough to get screen size chunk on
                scrollXDelta += (rect.left - screenLeft);
            } else {
                // get entire rect at right of screen
                scrollXDelta += (rect.right - screenRight);
            }

            // make sure we aren't scrolling beyond the end of our content
            int right = getChildAt(0).getRight();
            int distanceToRight = right - screenRight;
            scrollXDelta = Math.min(scrollXDelta, distanceToRight);

        } else if (rect.left < screenLeft && rect.right < screenRight) {
            // need to move right to get it in ll_buttonView: move right just enough so that
            // entire rectangle is in ll_buttonView (or at least the first screen
            // size chunk of it).

            if (rect.width() > width) {
                // screen size chunk
                scrollXDelta -= (screenRight - rect.right);
            } else {
                // entire rect at left
                scrollXDelta -= (screenLeft - rect.left);
            }

            // make sure we aren't scrolling any further than the left our content
            scrollXDelta = Math.max(scrollXDelta, -getScrollX());
        }
        return scrollXDelta;
    }

    @Override
    public void requestChildFocus(View child, View focused) {
        if (!mScrollViewMovedFocus) {
            if (!mIsLayoutDirty) {
                scrollToChild(focused);
            } else {
                // The child may not be laid out yet, we can't compute the scroll yet
                mChildToScrollTo = focused;
            }
        }
        super.requestChildFocus(child, focused);
    }


    /**
     * When looking for focus in children of a scroll ll_buttonView, need to be a little
     * more careful not to give focus to something that is scrolled off screen.
     * <p>
     * This is more expensive than the default {@link android.view}
     * implementation, otherwise this behavior might have been made the default.
     */
    @Override
    protected boolean onRequestFocusInDescendants(int direction,
                                                  Rect previouslyFocusedRect) {

        // convert from forward / backward notation to up / down / left / right
        // (ugh).
        // TODO: FUCK
        //        if (direction == View.FOCUS_FORWARD) {
        //            direction = View.FOCUS_RIGHT;
        //        } else if (direction == View.FOCUS_BACKWARD) {
        //            direction = View.FOCUS_LEFT;
        //        }

        final View nextFocus = previouslyFocusedRect == null ?
                FocusFinder.getInstance().findNextFocus(this, null, direction) :
                FocusFinder.getInstance().findNextFocusFromRect(this,
                        previouslyFocusedRect, direction);

        if (nextFocus == null) {
            return false;
        }

        //        if (isOffScreenH(nextFocus)) {
        //            return false;
        //        }

        return nextFocus.requestFocus(direction, previouslyFocusedRect);
    }

    @Override
    public boolean requestChildRectangleOnScreen(View child, Rect rectangle,
                                                 boolean immediate) {
        // offset into coordinate space of this scroll ll_buttonView
        rectangle.offset(child.getLeft() - child.getScrollX(),
                child.getTop() - child.getScrollY());

        return scrollToChildRect(rectangle, immediate);
    }

    @Override
    public void requestLayout() {
        mIsLayoutDirty = true;
        super.requestLayout();
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        super.onLayout(changed, l, t, r, b);
        mIsLayoutDirty = false;
        // Give a child focus if it needs it
        if (mChildToScrollTo != null && isViewDescendantOf(mChildToScrollTo, this)) {
            scrollToChild(mChildToScrollTo);
        }
        mChildToScrollTo = null;
        initAutoScrollBorder();
        // Calling this with the present values causes it to re-clam them
        //smoothScrollTo(getScrollX(), getScrollY());
        getScaleY();
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);

        View currentFocused = findFocus();
        if (null == currentFocused || this == currentFocused)
            return;

        // If the currently-focused ll_buttonView was visible on the screen when the
        // screen was at the old height, then scroll the screen to make that
        // ll_buttonView visible with the new screen height.
        if (isWithinDeltaOfScreenV(currentFocused, 0, oldh)) {
            currentFocused.getDrawingRect(mTempRect);
            offsetDescendantRectToMyCoords(currentFocused, mTempRect);
            int scrollDelta = computeScrollDeltaToGetChildRectOnScreenV(mTempRect);
            doScrollY(scrollDelta);
        }

        final int maxJump = getRight() - getLeft();
        if (isWithinDeltaOfScreenH(currentFocused, maxJump)) {
            currentFocused.getDrawingRect(mTempRect);
            offsetDescendantRectToMyCoords(currentFocused, mTempRect);
            int scrollDelta = computeScrollDeltaToGetChildRectOnScreenH(mTempRect);
            doScrollX(scrollDelta);
        }
    }

    /**
     * Return true if child is an descendant of parent, (or equal to the parent).
     */
    private boolean isViewDescendantOf(View child, View parent) {
        if (child == parent) {
            return true;
        }

        final ViewParent theParent = child.getParent();
        return (theParent instanceof ViewGroup) && isViewDescendantOf((View) theParent, parent);
    }

    /**
     * Fling the scroll ll_buttonView
     *
     * @param velocityY The initial velocity in the Y direction. Positive
     *                  numbers mean that the finger/cursor is moving down the screen,
     *                  which means we want to scroll towards the top.
     */
    public void computeMove(int startX, int startY, int velocityX, int velocityY) {
        int right = getChildAt(0).getWidth();
        int bottom = getChildAt(0).getHeight();
        mScroller.fling(getScrollX(), getScrollY(), velocityX, velocityY,
                0, Math.max(0, rightScrollBorder),
                0, Math.max(0, bottomScrollBorder), right / 10, bottom / 8);//overX,over允许溢出边界的距离，也是回弹的距离
        postInvalidateOnAnimation();

    }

    public boolean isNeedScrollBack() {
        int currentScrollX = getScrollX();
        int currentScrollY = getScrollY();
        //滑动停止的位置超出边界，需要回弹
        if (currentMaxScrollX < currentScrollX || currentMaxScrollY < currentScrollY || currentScrollX < 0 || currentScrollY < 0) {//mScroller.springBack(currentScrollX, currentScrollY, 0, currentMaxScrollX, 0, currentMaxScrollY)
            int deltaX = 0;
            int deltaY = 0;
            //超出左边界
            if (currentMaxScrollX < currentScrollX) {
                deltaX = currentMaxScrollX - currentScrollX;
            }//超出右边界
            else if (currentScrollX < 0) {
                deltaX = -currentScrollX;
            }
            //超出上边界
            if (currentMaxScrollY < currentScrollY) {
                deltaY = currentMaxScrollY - currentScrollY;
            }//超出下边界
            else if (currentScrollY < 0) {
                deltaY = -currentScrollY;
            }
            //回弹
            mScroller.startScroll(currentScrollX, currentScrollY, deltaX, deltaY, 500);

            //  postInvalidateOnAnimation();

            return true;
        }
        return false;
    }

    /**
     * {@inheritDoc}
     * <p>
     * <p>This version also clamps the scrolling to the bounds of our child.
     */
    @Override
    public void scrollTo(int x, int y) {
        // we rely on the fact the View.scrollBy calls scrollTo.
        if (getChildCount() > 0) {
            //约束滑动的X,Y边界
//            if (x < 0) {
//                x = 0;
//            }
//            if (y < 0) {
//                y = 0;
//            }
//            if (currentMaxScrollX - x < 0) {
//                x = currentMaxScrollX;
//            }
//            if (currentMaxScrollY - y < 0) {
//                y = currentMaxScrollY;
//            }
            if (x != getScrollX() || y != getScrollY()) {
                super.scrollTo(x, y);
            }
        }
        //  super.scrollTo(x, y);
    }

    private int clamp(int n, int my, int child) {
//        if (my >= child ) {//|| n < 0
//             /* my >= child is this case:
//              *                    |--------------- me ---------------|
//              *     |------ child ------|
//              * or
//              *     |--------------- me ---------------|
//              *            |------ child ------|
//              * or
//              *     |--------------- me ---------------|
//              *                                  |------ child ------|
//              *
//              * n < 0 is this case:
//              *     |------ me ------|
//              *                    |-------- child --------|
//              *     |-- mScrollX --|
//              */
//            return 0;
//        }
//        if ((my + n) > child) {
//             /* this case:
//              *                    |------ me ------|
//              *     |------ child ------|
//              *     |-- mScrollX --|
//              */
//            return child - my;
//        }
        return n;
    }

    public boolean isFlingEnabled() {
        return mFlingEnabled;
    }

    public void setFlingEnabled(boolean flingEnabled) {
        this.mFlingEnabled = flingEnabled;
    }

    private class ScaleGestureListener implements ScaleGestureDetector.OnScaleGestureListener {
        @Override
        public boolean onScale(ScaleGestureDetector detector) {

            float previousSpan = detector.getPreviousSpan();// 前一次双指间距
            float currentSpan = detector.getCurrentSpan();// 本次双指间距
            if (currentSpan < previousSpan) {
                // 缩小
                // scale = preScale - (previousSpan - currentSpan) / 1000;
                scale -= 0.1f;
            } else if (currentSpan > previousSpan) {
                // 放大
                // scale= preScale + (currentSpan - previousSpan) / 1000;
                scale += 0.1f;
            }
            if (scale < 0.5) {
                scale = 0.5f;
            } else if (scale > 1) {
                scale = 1f;
            }

//            if (myListener != null) {
//                myListener.onScale(scale);
//            }
            View childAt = getChildAt(0);
            ViewHelper.setScaleX(childAt, scale);// x方向上缩放
            ViewHelper.setScaleY(childAt, scale);// y方向上缩放
            float x = getScrollX();
            float y = getScrollY();
            float focusX = detector.getFocusX() + x;
            float focusY = detector.getFocusY() + y;
            //设置缩放的中心点，
            ViewHelper.setPivotX(childAt, focusX);
            ViewHelper.setPivotY(childAt, focusY);


            return false;
        }

        @Override
        public boolean onScaleBegin(ScaleGestureDetector detector) {
            return true;
        }

        @Override
        public void onScaleEnd(ScaleGestureDetector detector) {
            preScale = scale;// 记录本次缩放比例
            lastMultiTouchTime = System.currentTimeMillis();
        }
    }

    /**
     * 获取状态栏的高度
     *
     * @param context
     * @return
     */
    public void setStatusHeight(Activity context) {
        int statusHeight = 0;
        Rect localRect = new Rect();
        context.getWindow().getDecorView().getWindowVisibleDisplayFrame(localRect);
        statusHeight = localRect.top;
        if (0 == statusHeight) {
            Class<?> localClass;
            try {
                localClass = Class.forName("com.android.internal.R$dimen");
                Object localObject = localClass.newInstance();
                int i5 = Integer.parseInt(localClass.getField("status_bar_height").get(localObject).toString());
                statusHeight = context.getResources().getDimensionPixelSize(i5);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        mStatusHeight = statusHeight;
    }

    /**
     * 拖动item，在里面实现了item镜像的位置更新，item的相互交换以及GridView的自行滚动
     */
    private void onDragItem(int moveX, int moveY) {
        mWindowLayoutParams.x = moveX - mPoint2ItemLeft;
        mWindowLayoutParams.y = moveY - mPoint2ItemTop;
        mWindowManager.updateViewLayout(mDragImageView, mWindowLayoutParams); //更新镜像的位置
        // onSwapItem(moveX, moveY);
        mHandler.post(mScrollRunnable);
        View pointView = getPointView(moveX, moveY);
        if (pointView == mStartDragItemView) {
            return;
        }
        if (pointView != null && isScrollIn) {
            targetView = pointView;
            isScrollIn = false;
            isScrollOut = true;
            myListener.onDragInTargetItem(targetView);
        } else if (pointView == null && isScrollOut) {
            isScrollIn = true;
            isScrollOut = false;
            myListener.onDragOutTargetItem(targetView);
        }

        //父view自动滚动
    }

    /**
     * 当moveY的值大于向上滚动的边界值，触发GridView自动向上滚动
     * 当moveY的值小于向下滚动的边界值，触犯GridView自动向下滚动
     * 否则不进行滚动
     */
    private Runnable mScrollRunnable = new Runnable() {

        @Override
        public void run() {
            int deltaX;
            int deltaY;
            if (moveY < mTopAutoScrollBorder) {
                deltaY = -speed;
                mHandler.postDelayed(mScrollRunnable, 25);
            } else if (moveY > mBottomAutoScrollBorder) {
                deltaY = speed;
                mHandler.postDelayed(mScrollRunnable, 25);
            } else {
                deltaY = 0;
            }
            if (moveX < mLeftAutoScrollBorder) {
                deltaX = -speed;
                mHandler.postDelayed(mScrollRunnable, 25);
            } else if (moveX > mRightAutoScrollBorder) {
                deltaX = speed;
                mHandler.postDelayed(mScrollRunnable, 25);
            } else {
                deltaX = 0;
            }
            //当我们的手指到达GridView向上或者向下滚动的偏移量的时候，可能我们手指没有移动，但是DragGridView在自动的滚动
            //所以我们在这里调用下onSwapItem()方法来交换item
            // onSwapItem(moveX, moveY);
            int scrollX = getScrollX();
            int scrollY = getScrollY();
            //内容自动滑动到左右边界的时候，就设置X方向滑动变量为0，不再滑动
            if (scrollX + deltaX < 0 || scrollX + deltaX > rightScrollBorder) {
                deltaX = 0;
            }
            //内容自动滑动到上下边界的时候，就设置Y方向滑动变量为0，不再滑动
            if (scrollY + deltaY < 0 || scrollY + deltaY > bottomScrollBorder) {
                deltaY = 0;
            }
            if (deltaX == 0 && deltaY == 0) {
                mHandler.removeCallbacks(mScrollRunnable);
            }
            smoothScrollBy(deltaX, deltaY);
            // smoothScrollTo();
        }
    };


    //用来处理是否为长按的Runnable
    private Runnable mLongClickRunnable = new Runnable() {

        @Override
        public void run() {
            isLongClick = true; //设置可以拖拽
            //mIsBeingDragged=false;
            mVibrator.vibrate(50); //震动一下
            // mStartDragItemView.setVisibility(View.INVISIBLE);//隐藏该item

            //根据我们按下的点显示item镜像
            createDragImage(mDragBitmap, mDownX, mDownY);
        }
    };

    /**
     * 创建拖动的镜像
     *
     * @param bitmap
     * @param downX  按下的点相对父控件的X坐标
     * @param downY  按下的点相对父控件的X坐标
     */
    private void createDragImage(Bitmap bitmap, int downX, int downY) {
        mWindowLayoutParams = new WindowManager.LayoutParams();
        mWindowLayoutParams.format = PixelFormat.TRANSLUCENT; //图片之外的其他地方透明
        mWindowLayoutParams.gravity = Gravity.TOP | Gravity.LEFT;
        mWindowLayoutParams.x = downX - mPoint2ItemLeft;
        mWindowLayoutParams.y = downY - mPoint2ItemTop;
        mWindowLayoutParams.alpha = 0.55f; //透明度
        mWindowLayoutParams.width = WindowManager.LayoutParams.WRAP_CONTENT;
        mWindowLayoutParams.height = WindowManager.LayoutParams.WRAP_CONTENT;
        mWindowLayoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
                | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;

        mDragImageView = new ImageView(getContext());
        mDragImageView.setImageBitmap(bitmap);
        mWindowManager.addView(mDragImageView, mWindowLayoutParams);
    }

    private View getPointView(int mDownX, int mDownY) {
        RelativeLayout containerView = (RelativeLayout) getChildAt(0);
        for (int i = 0; i < containerView.getChildCount(); i++) {
            View childView = containerView.getChildAt(i);
            if (isPointOutItem(mDownX, mDownY, childView)) continue;
            return childView;
        }

        return null;
    }

    private boolean isPointOutItem(int mDownX, int mDownY, View childView) {
        if (childView == null) {
            return false;
        }
        int[] location = new int[2];
        childView.getLocationOnScreen(location);
        int x = location[0];
        int y = location[1];
        if (mDownX < x || mDownX > (x + childView.getWidth()) || mDownY < y || mDownY > (y + childView.getHeight())) {
            return true;
        }
        return false;
    }

    private void getPointOffsetofItem(int mDownX, int mDownY, View childView) {
        int[] location = new int[2];
        childView.getLocationOnScreen(location);
        int x = location[0];
        int y = location[1];
        mPoint2ItemTop = mDownY - y;
        mPoint2ItemLeft = mDownX - x;
    }

    /**
     * 停止拖拽我们将之前隐藏的item显示出来，并将镜像移除
     */
    private void onStopDrag(int x, int y) {
        // TODO: 2018/5/5 0005  判断up的位置是否落在某个item上方，如果是 调用接口提示数据更改
        View pointView = getPointView(x, y);
        if (pointView != null && pointView != mStartDragItemView && myListener != null) {
            myListener.onLongClickEnd(pointView, mStartDragItemView);
        }
        if (mStartDragItemView != null) {
            mStartDragItemView.setVisibility(View.VISIBLE);
        }

        removeDragImage();
    }

    /**
     * 从界面上面移动拖动镜像
     */
    private void removeDragImage() {
        if (mDragImageView != null) {
            mWindowManager.removeView(mDragImageView);
            mDragImageView = null;
        }
    }

    public void setOnLongClickListener(MyListener myListener) {
        this.myListener = myListener;

    }

    public void setScrollBorder(int x, int y) {
        if (x < 0) {

            leftScrollBorder = x;
        } else {

            rightScrollBorder = x - leftScrollBorder;
        }
        if (y < 0) {

            topScrollBorder = y;
        } else {
            bottomScrollBorder = y - topScrollBorder;

        }
    }


    public interface MyListener {
        void onLongClickEnd(View targetView, View dragView);

        /**
         * 长按滑动过程中，滑进某个item的上方
         *
         * @param view
         */
        void onDragInTargetItem(View view);

        /**
         * 长按滑动过程中，滑出某个item的上方
         *
         * @param view
         */
        void onDragOutTargetItem(View view);

        void onScale(float scale);
    }


}